By the terms of Michigan’s prevailing wage statute, the Michigan Department of Labor and Economic Growth is required to look at union rates exclusively in determining the prevailing wage. At the time the state law was passed, this might have been a reasonable way to find a prevailing wage. While there are no reliable figures for the state prior to 1983, it is estimated that in 1966, just one year after Michigan’s law was passed, union members made up 41.4 percent of the U.S. construction work force.[25] Given Michigan’s history as a heavily unionized state, it is very likely that half or nearly half of Michigan construction workers were covered by collective bargaining agreements, and the union rates generally did prevail at the time Michigan’s law was passed.

But since 1966, the percentage of American workers who belong to unions has been inexorably dropping, and workers in Michigan and the
construction industry are no exception.* According to an analysis of U.S. Census Bureau data, the trend for the last 20 years has been downward: In 1986, 32.8 percent of construction workers in Michigan were union members; by 1996, that figure was 25.6 percent; and in 2006, only 22.1 percent of Michigan construction workers were union members.[26] Hence, Michigan’s prevailing wage law is based on wage rates for a shrinking minority of construction workers.

* Admittedly, this conclusion is based on two sources using different methodologies and covering separate time periods, but both sources have one thing in common – significant decreases in union membership among construction workers. Leo Troy and Neil Sheflin estimate that union members made up 41.4 percent of the national construction work force in 1966, but only 23.5 percent in 1984. (U.S. Union Sourcebook, 1st ed. ([IRDIS: West Orange, NJ, 1985], 3–15). Hirsch and MacPherson estimate that nationally union membership declined among construction workers between 1986 and 2006 from 23.3 percent to 14.0 percent. These estimates are available online at
http://www.trinity.edu/bhirsch/unionstats.